title: Diurnal vertical migration of Cochlodinium polykrikoides during the red tide in Korean coastal sea waters.
abstract: The diurnal vertical migration of Cochlodinium polykrikoides (C. polykrikoides), which caused a red tide in the Korean coastal waters of the East Sea/Sea of Japan in September 2003, was examined by determining the time-dependent changes in the density of living cells in relation to the depth of the water column. The ascent of this species into the surface layer (depth of water 2 m) occurred during 1400-1500. The descent started at 1600 and a high distribution rate (86%) at 15-20 m was observed at 0300. During the ascent, the cells were widely distributed at each depth level from 0600 hr and at 0800-1100, the cells were primarily distributed in the middle layer (0-6 m). The concentration of dissolved inorganic nitrogen was generally < or = 2.86 micromol l(-1), but at 1400-1500, the concentration in the surface layer reduced to < or = 0.14 micromol l(-1). Moreover, the concentration gradually increased as the depth increased to > or = 5 m. These results showed that the nutrient-consumption rate associated with the proliferation of C. polykrikoides during a red tide is more influenced by the inorganic-nitrogen resources ratherthan the inorganic-phosphorus compounds.
authors.affiliation: East Sea Fisheries Research Institute of NFRDI, Gangrung - 210-861, Korea. biochip@nfrdi.go.kr
authors.forename: Young Sug
authors.initials: YS
authors.lastname: Kim
authors.forename: Chang Su
authors.initials: CS
authors.lastname: Jeong
authors.forename: Gi Tak
authors.initials: GT
authors.lastname: Seong
authors.forename: In Sung
authors.initials: IS
authors.lastname: Han
authors.forename: Young Sik
authors.initials: YS
authors.lastname: Lee
mesh_terms: D002940:Circadian Rhythm; D004141:Dinoflagellida / Q000502:physiology*; D017753:Ecosystem; D004784:Environmental Monitoring; D057097:Harmful Algal Bloom; D009792:Oceans and Seas; D056910:Republic of Korea